Iowa's Greg Castillo catches the game-ending interception in double overtime against Michigan State on Saturday.AP Photo

EAST LANSING -- Michigan State's offense remained on the field, players motionless and seemingly in shock.

Quarterback Andrew Maxwell had a second-down pass tipped at the line of scrimmage, only to be intercepted by Iowa's Greg Castillo, sealing the Spartans' 19-16 double-overtime loss.

Maxwell's throw was deflected at the line by Iowa's Louis Trinca-Pasat. It then bounced off wide receiver Keith Mumphery's hands and into Castillo's.

"It was so final," Maxwell said. "I've obviously never been part of an overtime game before as a starter and the fact that it just kind of ended ... it was difficult to let that sink in and really realize that's it."

The loss leaves Michigan State 4-3 overall and 1-2 in the Big Ten heading into next week's game at rival Michigan.

Mumphery finished with four receptions for 71 yards, and regretted not being able to pull in the final pass.

"The ball was tipped, but I still got to make that catch," Mumphery said. "No matter what's the situation, as a receiver my job is to block and catch the ball. When my number's called, I've got to catch it."

Maxwell blamed himself for not completing the pass, but was unaware of the initial deflection at the line when speaking with reporters after the game.

"Lack of accuracy, it was too high," Maxwell said. "Obviously in conditions like this, if I can it down around his chin, even if he doesn't catch it, it gets knocked down. Little things."

After Michigan State forced Iowa into a 42-yard field goal on its possession of the second overtime, the situation was clear for the Spartans.

A touchdown wins it, a field goal forces a third overtime and a turnover ends not only the game but possibly Michigan State's hopes at reaching the Big Ten championship game in Indianapolis.

Michigan State's Mark Dantonio always emphasizes that football is a "game of inches." The latest example wasn't in the Spartans' favor.

"The ball gets tipped right to the defender," Dantonio said. "As promising as things look it can change immediately, and it's tough. When you're on the sidelines it's very difficult to handle, and you're just sort of stunned."